Torque ripples and estimation performance of high frequency signal injection based sensorless PMSM drive strategies

The developed nonlinear permanent magnet synchronous machine (PMSM) model established a virtual model to simulate and assess the sensorless drive schemes for PMSMs avoiding the experimental trial and error method. In this paper, three sensorless PMSM drive schemes are investigated and compared, which are all based on the high frequency signal injection. The nonlinear PMSM machine model is employed to accurately simulate the machine performance and to analytically assess the efficiency of the sensorless algorithm. Both the structural and saturation saliencies are incorporated in this comprehensive model. The comparison of the machine torque ripples induced by excitation signals are carried out. The magnitude of injected signal and recordable rotor position information are considered together as the efficiency of the estimation algorithm. Additionally, the implementation and signal process computing costs are considered for all the schemes. Finally, a comprehensive comparison of all the methods is developed.